Consider the following code example:
fn main() {
let mut arr : Vec<Vec<usize>> = Vec::new();
for _ in 0..10 {
arr.push(Vec::new());
}
for i in 0..10 {
arr[i].push(i);
arr[i].push(i+5);
}
for x in arr[0].iter() {
arr[1].push(*x);
}
println!("Test {:?}", arr[1]);
}
Which fails to compile with the following error:
error[E0502]: cannot borrow `arr` as mutable because it is also borrowed as immutable
I gather this is because I performed the immutable borrow of arrby calling iter() and then modifying arr in the same loop (thereby using a mutable borrow). This behavior of the rust compiler makes total sense to me to prevent changing the very thing that is being iterated over during a for loop, however in this specific case I know that adding to arr[1] won't change arr[0]. So how do I tell this rust compiler and compile this program without needing to use clone?
